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32 Installing the System Piping
3.5.2 System Application - Zone System with Zone Valves (Primary/Secondary Piping)
Make-up Water
Pressure reducing valve
Backflow preventer
Additional Zone
Zone #2
Zone #1
System Pump
Air Separator
Expansion Tank
Not to exceed 4 pipe Dia or Max. 12"
Zone Valve
(Typical)
Return filter
Boiler Pump
Note
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System application drawings are intended to explain the system piping concept only.
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Install a filter in the system return to remove foreign objects from the system. Foreign objects inside
the system may result in abnormal system operation.
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Refer to “3.3 Filling the System” on page 28 for make-up water connections and refer to the
requirements of your local codes to ensure compliance.
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Use a pump with an integral check valve or install a check valve at the pump outlet.
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Refer to “3.6.5 Wiring Diagram - Zone Valve System” on page 41 for wiring connections.
Summary of Contents for NFB-175H
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